The ultimate goal of this Fast Track small business research project is to improve the vision of people who have abnormal corneal conditions that substantially alter the corneal shape such as keratoconus and corneal transplant. Patients with abnormal corneal shapes have substantially larger magnitudes of both lower-order and higher-order aberrations compared to normals. Even with optimal sphero-cylindrical correction, the uncorrected residual higher order aberrations cause a clinically significant degradation in visual quality. Correcting the higher order aberrations has been challenging due to both the inability to measure highly aberrated eyes and to manufacture a contact lens with an irregular (non-rotationally symmetrical) surface profile. This research project is designed to address these current barriers by developing a commercial grade, large dynamic range wavefront sensor, together with freeform machining technology to fabricate wavefront- guided customized soft contact lenses. In Phase 1, we will demonstrate the feasibility of freeform machining technology to create an irregular (non-rotationally symmetrical) lens surface profile capable of correcting higher order aberrations (Phase 1 Aim 1) and minimizing unpredictable translation and rotation of the lens on eye by customizing the back surface of the lens matched to the irregular anterior surface of the cornea (Phase 1 Aim 2). In Phase 2, Aim 1, we will develop a commercial-grade large dynamic range wavefront sensor equipped with user-friendly software for wavefront analysis and contact lens design. In Phase 2, Aim 2, we will evaluate methods to maximize the visual benefit with the wavefront-guided lens by minimizing the adverse impact of residual lens movement on correction performance. Then, in Phase 2, Aim 3, we will compare the visual outcomes with this customized soft contact lens (CustomEyes) to those with soft contact lenses designed to fit keratoconic eyes but with conventional sphero-cylindrical optics to determine the clinical feasibility and the true visual benefit provided by the wavefront guided customized soft lens in keratoconus patients.